PUC gets up-close look at water treatment plant, flaws and all

PUC officials, from left, Tom Ahern (obscured), Kevin Lynch and John Bell watch as water gushes down a concrete sluice en-route to the Blackstone River at the aging water treatment plant in Woonsocket Wednesday. Photo/Ernest A. Brown

WOONSOCKET – As the cascade of frothy water gushed through a concrete sluice en-route to the Blackstone River, it looked as pristine as a waterfall in the Rocky Mountains.
The observers from the state division of Public Utilities and Carriers (PUC) seemed disappointed.
“When does the dirty water come out?” one asked.
Acting Water Supt. Marc Viggiani paused a moment before answering.
“Soon.”
The so-called “dirty water” discharged from the 50-year-old Charles Hamman Water Treatment Plant on Manville Road is central to what’s driving one of the hottest debates in city government in years. When it does come out, the concentrated backwash from the cavernous, cylindrical filters at the plant looks more like coffee than water.
Somehow, it’s surprising that that the brackish liquid is odorless.
Tens of thousands of gallons of filter backwash from each of three 750,000-gallon filter tanks are dumped into the Blackstone River every week. The state Department of Environmental Management has ordered the city to stop the practice no later than May 2016, citing concerns about the effect of the chemical-laden soup on fish and other river life.
On a raw and cloudy day earlier this week, Mayor Leo T. Fontaine and Public Works Director Sheila McGauvran invited members of the PUC to see the operations of the plant – and its deteriorating condition – first-hand. The observers included PUC Administrator Tom Ahern, Chief Financial Officer John Bell, Chief Engineer Al Mancini, and Deputy PUC Administrator Kevin Lynch.
If the city builds a new plant, it will need the approval of the PUC to finance the project through the state Clean Water Finance Agency.
“We thought it was important for officials from the PUC to see for themselves the kind of condition the plant is in,” said Fontaine. “We don’t think it’s something that’s in the best interest of city residents to maintain.”
Though the city could probably eliminate the filter backwash for about $5 million, according to McGauvran, she and Mayor Fontaine say that doing so would be a case of throwing good money after bad because the plant itself is technologically obsolete and near the end of its functional lifespan. They say the most cost-effective way to deliver water to ratepayers in the long run is to replace the plant at a cost of about $50 million, and to allow a private company to operate the plant instead of city workers.
With the financially-teetering city under the control of a state-appointed Budget Commission, and city residents facing steep tax hikes, the plan has come under attack as too costly and anti-labor. Plant employees say privatization will cost jobs and result in higher costs for ratepayers. Some say the plant could last another 20 years and the city is rushing to replace it at a time when it’s least affordable.
The tour was the mayor’s effort to rebut claims about the projected longevity of the plant with the plainest evidence available: the plant itself.
“Anyone who has seen the plant up close realizes how foolish that assumption is,” said the mayor. “We can’t just sit back and drag our feet while the plant crumbles. If this facility ever failed the results would be catastrophic.”
After a top-to-bottom tour of the facility, Ahern, the PUC administrator, appeared to have reached a similar conclusion.
“I see a plant that is technologically in need of upgrade,” he said. “They have a system that works, but you have to plan for the future and they should give serious thought to having a new water treatment plant. You can only put a Band Aid on a problem so long.”
Ahern said he has been administrator of the PUC for 17 years and during that time every water district in the state has undergone a major upgrade with the exception of Woonsocket. That includes Providence, Pawtucket, Kent, Newport and United Water in South Kingstown.

BUILT IN 1950 by the R. Zoppo Corp. of Stoughton, Mass., the plant’s most visible features are three 750,000-gallon filter tanks and two 500,000-gallon “clearwells.” Gravity feeds water into the plant from city-owned reservoirs in nearby North Smithfield, while a system of heavy-duty pumps and mains draws the supply into the filter tanks, the clearwells and, a half-mile away, high-service storage vessels.
Mid-way through the trip from the reservoir to the clearwells, the water is mixed with inert polymers and a chemical called alum to pull out sediments and other impurities.
The water is also treated with fluoride, an optional additive that is supposed to prevent tooth decay, and chlorine. After the water is treated, it’s pumped over to the clear wells, where it sits for about an hour to give the chlorine time to do its job of killing potentially harmful microorganisms before it’s pumped on to storage.
The charcoal-activated filter tanks are completely emptied into the Blackstone River several times a week, a process that takes about 45 minutes.
The filter backwash is a kind of concentrated broth that contains residues of all the processing chemicals and indigenous organic impurities of raw water before filtration begins. Mostly, the brownish stuff settles into the tanks through gravity, but it builds up so quickly that it must be purged from the system on a regular basis to keep drinking water clean.
Before the filter backwash is released into the Blackstone River, it’s mixed with powdered lime to make sure the ph-level of the discharge is neutral enough to avoid harm to fish and other river creatures. The water division buys the stuff by the ton, stacking it on pallets inside the plant.
Scores of motorists who drive by the plant on any given day can easily see that the huge filter tanks and clearwells are, at a minimum, in need of major cosmetic work. Once, the tanks were all painted sky-blue, but the paint is flaking off and giving way to a burnt orange color from the rust building up on the structural steel below the deteriorating paint. Rust coats the interior of the filter tanks, too, a problem easily visible from a catwalk on the inside of the giant cylinders.
The clearwells, the last stop in the treatment process before the water comes out of household taps, are in worse condition than the filter tanks. They are nearly encased in a coating of thick rust as the paint has eroded away almost entirely. At the base of the structures, which sit on concrete pads, the steel is corroding and the rust-stained concrete is disintegrating.
In the bowels of the plant, paint is also flaking off steel pipes five feet in diameter. A leak or two has sprung in the pipes, a problem workers deal with by positioning plastic buckets under them to collect the drips.
“There are people who contend this plant will last another 20 years,” says McGauvran, the public works director. “There’s not even a chance that’s going to happen.”
The best evidence about the longevity of the plant comes from a study commissioned by the city in 2002, she says. Thielsch Engineering of Cranston determined that the structural steel housing of the filter tanks and clearwells was sound enough to last five to 10 years. The base of the tanks weren’t tested because the technicians couldn’t reach them.
One way to interpret the Thielsch findings is that the plant is already on borrowed time, city officials say.
McGauvran said the city could address the backwash issue by capturing the tainted runoff and treating it. That would mean building a pipeline to ferry the backwash to a self-contained treatment facility. The backwash would then be channeled to the sewer system, where it would get another round of cleansing in the wastewater treatment plant before being discharged into the Blackstone River.
The cost of building a backwash treatment system would easily reach $5 million, according to McGauvran. But even if the city spent that money, it would still be left with an antiquated water treatment plant with a costly new gadget attached to it. The core facility would still be substandard and at risk of imminent failure.
If the Fontaine administration has its way, it will build a new plant on some 19 acres of land off Jillson Avenue. The facility would have a production capacity of 8 million gallons per day, substantially less than the existing plant was designed for – in a bygone era of water-hungry mills and factories. McGauvran said she is eyeing a “modular” design for the plant, so it could be quickly enlarged to accommodate potential new industries.
The new facility will not employ technology that requires filter backwashing to produce safe, clean drinking water, she said.
Though the price tag is only a preliminary estimate, officials say they could cut operating costs by $1 million a year if the plant is designed, built and managed by an outside contractor.
Reacting to the din of protest over the plans, the budget commission tabled them pending more study. The commission voted this week to hire a consultant to see if the privatization model will actually result in the savings the Fontaine administration claims it will.
One official who isn’t sold on privatization is Viggiani, the acting water superintendent. The leader of the tour, Viggiani said he isn’t opposed to replacing the plant, but he thinks ratepayers would be better served if those who run the new facility are employed by the city.
“Privatization adds costs to the ratepayers,” said Viggiani. “We’re non-profit. Our main thing is quality water and keeping the price as low as possible.”